Method of Making Cellular Materials from Red Oak Bark

A laboratory process for forming a panel from milled hard wood bark and a foamed polyvinyl acetate adhesive is described. The aim of the project was to produce a material with a density below .5 g/cm3 and adequate strength, with an OD binder content of 15 to 26 percent. Plasticized and unplasticized PVA emulsions were foamed, combined with the milled bark, poured into an aluminum tray, and placed in a forced draft oven to dry at 50?C. When the cast material reached a semisolid consistency, the temperature of the oven was raised to 105?C. The material dried within 24 hours. Modulus of rupture decreased with a decrease in the amount of binder, and material with the plasticized binder were much weaker than those with the unplasticized binder. Volumetric swelling was 10 to 12.9 percent after 3 hours of water immersion. The cellular materials showed excellent paintability, machinability, and were successfully laminated with plywood, paper, and aluminum foil.

You must be logged in to download any documents. Please login (login accounts are free) or learn how to Become a Member